Thermal inkjet technology is a significant technology that finds wide use. However, it is limited to using carrier liquids such as water that boil effectively at temperatures reached in the printhead, resulting from the selective application of a current to resistors that cause bubbles in the ink to form, thereby expelling, or jetting, droplets of ink through nozzles.
There are, however, applications which require jetting fluids that do not boil, either because their boiling temperatures are high or they do not have a clearly-defined phase transition which leads to a smoothed out transition to gas. In these cases, printheads based on piezoelectric technology are used. That is, a piezoelectric element is caused to vibrate, thereby jetting droplets of ink through nozzles. These piezoelectric printheads are much more difficult to make and are more expensive. Extension of thermal jetting technology to inks currently requiring piezoelectric printheads may have a significant impact on the thermal inkjet printer market. Such an extension may potentially enable low cost, high quality commercial graphics printing currently under development that assume the use of piezoelectric printheads.